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Maps Show Mars Was Once More Like Earth
vrioux writes "NASA scientists have discovered additional evidence that Mars once underwent plate tectonics, slow movement of the planet's crust, like the present-day Earth. A new map of Mars' magnetic field made by the Mars Global Surveyor spacecraft reveals a world whose history was shaped by great crustal plates being pulled apart or smashed together. ."
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I wouldn't be surprised to find that the majority of solid planets that we examine undergo the same basic geologic mechanisms. Tectonics, subduction, spreading, etc, are probably far more common in the universe than we think.
Be a real patriot: Question authority. Think for yourself. Formulate your own conclusions.
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Seeing as how we do not behave exactly like every other animal...
Please tell me you're being facetious. I'm sure you'll find that no two types of animals behave *exactly* alike. However, a whole lot of them (including us), do exhibit many similar behaviours.
Be a real patriot: Question authority. Think for yourself. Formulate your own conclusions.
Probably the wars they fought over oil. That's why we won't find any there now. Come to think of it, someone should probably tell Bush that. I'm convinced that he's only pushing his space exploration mandate because he thinks there's WMDs on the moon and trillions of barrels of oil on Mars. (for those of you who are going to mod me down as a troll [and I know you're there], it's a JOKE. get a sense of HUMOUR)
Real_men_don't_need_spacebars.
... it also appears to have been ruled by giant purple spiders.
Rubbish. We came from the Pak homeworld.
In other words, no. We, as in humans, didn't come from Mars. We're definitely mammals, closely related to the other great apes. It's about as plain as you could ask for at every level from DNA right through to gross anatomy.
It is conceivable that life originated on Mars and spread to Earth in the days of nothing but single-celled organisms, but that's quite another matter.
Real Daleks don't climb stairs - they level the building.
Earth not center of universe, other planets similar.
Similar is not the same thing as "alike". We're still grasping with whether the various effects we see on Earth exist on other planets. Even if we find that these effects are common, we're still left with a quandry about Earth itself. There are just so many little things about the Earth that are balanced in favor of life (e.g. Distance from Sun, size of star, size of planet/gravity, magnetic field strength, atmosphere composition, etc.), that it's statistically hard to say that there's life anywhere we'd be able to reach before we're long extinct.
Look up the Drake Equation for more info on why the Earth may very well be "the center of the Universe". (At least as far as life is concerned.
Here's the journal abstract:
0 2v1
http://www.pnas.org/cgi/content/abstract/05074691
"Mars currently has no global magnetic field of internal origin but must have had one in the past, when the crust acquired intense magnetization, presumably by cooling in the presence of an Earth-like magnetic field (thermoremanent magnetization). A new map of the magnetic field of Mars, compiled by using measurements acquired at an 400-km mapping altitude by the Mars Global Surveyor spacecraft, is presented here. The increased spatial resolution and sensitivity of this map provide new insight into the origin and evolution of the Mars crust. Variations in the crustal magnetic field appear in association with major faults, some previously identified in imagery and topography (Cerberus Rupes and Valles Marineris). Two parallel great faults are identified in Terra Meridiani by offset magnetic field contours. They appear similar to transform faults that occur in oceanic crust on Earth, and support the notion that the Mars crust formed during an early era of plate tectonics."
" Seeing as how we do not behave exactly like every other animal, would there be a way that we could have come from Mars? " It would be damn near impossible for humans and chimps to be so similar genetically. Species don't evolve toward eachother genetically.
Does that mean the Earth will end up like Mars in the future?
And how will this data help us terraforming Mars?
Far from answering, I think this only leaves us with more questions asked.
Martians are NOT amused by this comparison. They find it degrading, humiliating and defamatory.
"Earthlings have never come close to inventing a Illudium PU-36 Explosive Space Modulator, nor can the 19.7 km height of Mt. Everest even touch Olympus Mons with an altitude of 27 km!", says Mars local, Marvin.
He who knows best knows how little he knows. - Thomas Jefferson
All planets (like our own) which have a dynamic liquid core have magnetic fields. The strength of the field depends on how large and dynamic the molten core of the planet remains. When planets form, they start as a liquid lava rock, and slowly cool over millions of years. As they cool, the outer crust (or mantle) solidifies, while the core remains molten. This is true of any solid planet (not gas giant) therefore any rock-type planet would most likely of had a magnetic field at one time. Mars unfortunately is far enough from the sun that it has cooled to great depth inside the planet, reducing its liquid core to a very small percent of its original size, reducing and almost eliminating its magnetic field, which is at present very weak. Another proof of this is the lack of volcanism on Mars, which by examining the topographic features was once very active.
I think it's far more likely we came from Golgafrincham. How else could we explain our penchant for sanitizing telephones?
We're incredibly similar to every other animal - same basic chemistry, most of our genome the same. We have the same ancestors as every other living thing on this rock. A better (and open) question is whether all life on Earth is descended from (primitive) life that originated on Mars and was carried here by meteorites before Mars became uninhabitable.
I am trolling
that it's statistically hard to say that there's life anywhere we'd be able to reach before we're long extinct.
:o)
Similar life.
Life would still have the potential to exist elsewhere, but would have to adapt to a different environment. As a result it could exist but would probably not resemble anything we've seen before... we may not even know it if we did find it.
No no you guys have it all wrong. The Flying Spaghetti Monster reached down his noodley appendage and created a Mountain, Trees and a Midget. This ape business are lies spread by the non-FSM Believers. They shall never know what heaven is like, with it's stripper factory and beer volcano!
This is a perfect example of why you should always back up your work, too bad it would take up like, 65535TB of space to back up our entire planet.
It's never just a game when you're winning. - George Carlin
Life would still have the potential to exist elsewhere, but would have to adapt to a different environment.
This is a fairly common theory (especially in the wake of the early findings that the other planets in the Solar System are uninhabitable by humans), but our studies of our own solar system suggest it to be untrue. If life were as adaptable as suggested, then we'd find inflatable beings on Jupiter, Crystaline entities on Venus, creepy crawlers on Mars, and other life forms well suited to their environment.
Yet no such creatures have ever been found. Hope is still held that water creatures may be found on Jupiter's Icy Moons (specifically Europa), but we've pretty much exhausted the remainder of the Solar System.
Turning back inward toward Earth, we can't find life in many combinations. Pretty much all life on Earth follows the pattern of Carbon-basis with DNA information storage. About the most extreme variations are the circulatory systems of animals, with some having Copper-based blood.
Some organisms are able to survive extreme conditions, but they tend to not actually thrive in such environments. There are no signs of life that has specifically adapted to survive in conditions equating that of the more extreme planets. Even the Silicon-based Lifeform theory suffers heavily from a lack of any known examples.
While we occupy only an insignificant portion of the universe, our best evidence to date suggests that we may be far more alone than we might have hoped.
P.S. The Wikipedia article on The Fermi Paradox goes over many of these points in detail.
I once read an interesting story about some astonomer who believed that a long time ago Mars' orbit once was highly eliptical and crossed Earth's orbit and there was a near collision. Mars used to have oceans that alternatively froze solid and melted & boiled during it's highly elliptical orbit around the Sun until a very close encounter with Earth, where the two planets' gravities caused them to do a quick dance around each other during the near-collision, slinging off most of Mars' water which then was captured by the Earth's gravity and eventually fell into our own oceans, then Mars itself got slung outward towards it's current orbit where it collided with another small planetoid, the collision resulting in the formation of the asteroid belt and Mars' current stable orbit that is vastly less eliptical that before, but still not "almost circular" like Earth's orbit..
Plate tectonics takes millions of years. Be patient.
We behave a lot more like the animals on Earth than we behave like all the animals we know of on Mars. (I.e. none)
Besides, what's with this "exactly" requirement anyhow? No two animals (or people, if you think we mustn't be counted as animals) behave exactly like each other either. Maybe we all come from different planets! There's a planet somewhere that's full of exact copies of me!
(And there's a world filled with nothing but shrimp. I grew tired of that world quickly.)
Or (like the other poster said), maybe we come from Pak. That's a hell of a lot more likely than that Adam and Eve came from Mars.
Nah. Eve was faking it.
Don't know if this is THE map, but it is a map of Mars Crustal Magnetic Field Remnants: http://photojournal.jpl.nasa.gov/catalog/PIA02819
This is a fairly common theory (especially in the wake of the early findings that the other planets in the Solar System are uninhabitable by humans), but our studies of our own solar system suggest it to be untrue. If life were as adaptable as suggested, then we'd find inflatable beings on Jupiter, Crystaline entities on Venus, creepy crawlers on Mars, and other life forms well suited to their environment.
Yet no such creatures have ever been found. Hope is still held that water creatures may be found on Jupiter's Icy Moons (specifically Europa), but we've pretty much exhausted the remainder of the Solar System.
I'm going to have to argue with that. To be perfectly honest with ourselves, we can't say whether life only exists on a physical plane, or a mixture of magnetic, physical, spritual, gaseous.. we have no idea. It could be that life is abundant in forms we just haven't had the opportunity (capability) to discover yet. When one looks at areas that now seem unihabited, it seems impossible that they ever were. At present, desert covers a large part of Australia, The Great Sandy Desert, The Gibson Desert and the Great Victoria Desert combine to fill more than half of Western Australia. It was covered by large sheets of ice before that, and before that by a shallow ocean, which was most defintely teeming with life. The south pole has produced palm tree fossils. To a temporary observer (as we are to the celestial bodies), the south pole seems dead. it was once covered in life. Things change, things move, and accidents happen. Just because our sister and brother planets look devoid of life now, doesn't mean they are or have been. Or will be for that matter.
** "It's not my job to stand between the people talking to me, and the ones listening to me." -- Pego the Jerk
There are just so many little things about the Earth that are balanced in favor of life (e.g. Distance from Sun, size of star, size of planet/gravity, magnetic field strength, atmosphere composition, etc.)
The distance from the sun, is not as important as it seems to be. The habitable zone has not been at 1AU at all times and it's going to change again in the future. There was a time when Mars was in the habitable zone and Earth was not. Similarly, when the sun will get older and on its way of becoming a red giant, Mars will again be in the habitable zone while Earth will be as hot as Venus.
The size of a planet and its gravity doesn't necessarily favor or hinder the development of life, as long as you don't take the extremes into account(ie. life would most likely not develop on an asteroid or a gas giant, though there could be exceptions). Mars is a small rocky planet with a gravity of 0.376 Gs which is quite low for humans. But that doesn't mean life didn't exist there. Earth's 1G is not some kind of universal standard for life. It's just the gravity, earth species live on. The same goes for atmospheric composition and magnetic field strenght. It's the enviroment we evolved and live in, not a universal standard. Humans would have as hard a time adapting to a lower/higher G enviroment, or to a deviant atmospheric composition, as a lifeform from somewhere else would have on Earth.
Also don't forget evolution. Life can adapt to a changing enviroment. If we send humans to live on Mars, after several generations, their successors won't be able to live on Earth's gravity. Which btw I think it's the key for colonization of other planets. If we ever find a way to accelerate evolution changes on ourselves, it'd be easier to do this instead of terraforming other planets.
VStrider.
To me, the best evidence for water is this map, which they always show at NASA presentations on Mars. It's a topographic map colored by altitude, and you see that the areas below a certain depth are almost completely crater-free, contrasted strongly with the areas above that depth. This, to me, is a really, really strong argument that it was once covered in water and had a coastline.
Looking at that map always makes an Earth-like Mars seem much more real to me.
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my error, I am only humanoid
He who knows best knows how little he knows. - Thomas Jefferson
When I interned at NASA/Langley Research center, I heard constantly about the ARES Project, which they're going to use to survey Mars's magnetic field in much greater detail than the global surveyor (among other things).
And it will be the first airplane flight over another planet's surface, just 100 years after the Wright brothers first did it here.
xkcd.com - a webcomic of mathematics, love, and language.
Mars' atmosphere is drastically thinner than ours, and that is assumed to be in a large part due to the smaller size. The gravitational pull simply can't maintain a thick atmosphere, and Mars' size is such that the core has cooled off, and techtonic activity has stopped. Lack of techtonic activity means that atmospheric gasses are no longer being replenished. It may be possible that life could exist without an atmosphere, but it seems very unlikely to me. There would at least need to be a liquid medium to distribute metabolic chemicals (such as CO2 and O2 on earth) to allow for life to have the proper energy to survive. On Mars this would have to be on the surface, as the lack of techtonic activity means there would be no thermal vents such as on earth which provide another chemical gradient which allows some forms of life to survive. I don't have a problem seeing that life could have existed at one time on mars, but I highly doubt that it is currently there. There may be some remnant organisms in deep deep stasis which are basically waiting for favorable conditions to revive, but I personally do not call that currently living.
I'll never make that mistake again, reading the experts' opinions. - Feynman
Yes, yes you all did.
Now, if you breeders would simply shut up and let us Adults do the thinking, things would get better.
Sincerely, Brennan-monster.
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
A better question? An open question? Really!?
Not meaning to troll, but how exactly would a meteor jump or ricochet off mars and impact Earth? The idea just seems damned far-fetched. And wouldn't the atmospheric burn leaving mars and impacting earth and months or years of hard vacuum time do a nice job of sterilizing most things? And if this idea you posit says earth's organisms needed to come from Mars, where'd Mars get 'em?! After all, any creation story that posits that it is 'monkeys all the way down' loses my confidence pretty damn fast.
Given the huge range of temperatures, minerals, electrostatic activity, etc. here on earth, seems easier to imagine various 'crawled out of primordial soup' origin theories to space debris carrying lucky spores or enzymes. I mean, I like my infinite-improbabilities when they come packaged in a world that rolls the dice a millions of times per second for a few billion years.
Again, I don't mean to troll. We can't prove or disprove what you're suggesting, but your suggestion starts with 3 or 4 soon-to-be-tested requirements (residue of life-supporting ecology on mars, evidence of life on mars, that life's genetic resemblance to earth life, matching timelines). I even like seeing scientific trial-ballons like yours. But your idea seems astronomically unlikely given the alternatives.
Hmmm, maybe Mars was Earth version 1. Then the designer addressed the defects and came out with version 2.
The more you regulate a company, the worse its products become.
It is very uncommon, and the idea that they're from Mars is a VERY tenous idea at best. According to http://en.wikipedia.org/wiki/Martian_meteorite the idea is basically, "It doesn't look like it is from here, IT MUST BE FROM MARS."
Not exactly what I'd call science. I'd tend more to calling it "making shit up".
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba